Temperature effects on dislocation core energies in silicon and germanium

Abstract

Temperature effects on the energetics of the 90-degree partial dislocation in silicon and germanium are investigated, using non-equilibrium methods to estimate free energies, coupled with Monte Carlo simulations. Atomic interactions are described by Tersoff and EDIP interatomic potentials. Our results indicate that the vibrational entropy has the effect of increasing the difference in free energy between the two possible reconstructions of the 90-degree partial, namely, the single-period and the double-period geometries. This effect further increases the energetic stability of the double-period reconstruction at high temperatures. The results also indicate that anharmonic effects may play an important role in determining the structural properties of these defects in the high-temperature regime.

arXiv comment8 pages in two-column physical-review format with six figures

References in corpus (6)

• Interatomic Potential for Silicon Defects and Disordered Phases
• Environment Dependent Interatomic Potential for Bulk Silicon
• A period-doubled structure for the 90-degree partial dislocation in silicon
• Structure, barriers and relaxation mechanisms of kinks in the 90-degree partial dislocation in silicon
• Core reconstruction of the 90-degree partial dislocation in non-polar semiconductors
• Stability of the Period-Doubled Core of the 90-degree Partial in Silicon

Cited by in corpus (3)

• Harnessing dislocation motion using an electric field
• Theoretical study of kinks on screw dislocation in silicon
• Stability of undissociated screw dislocations in zinc-blende covalent materials from first principle simulations